About 13.7 billion years ago
The Big Bang Theory states that the universe started about 13.7 billion years ago, and before that, everything was in 1 singularity.
Heat rises therefore the heat from the fire rises up to your hand... i didnt have any answer choices to work with sorry
The functions of angles are used to find unknown lengths or angles that can't be measured, in terms of known quantities. The trig functions of angles are ratios of lengths, so they're bare naked numbers without units.
